Main Purpose of Sucralfate
Sucralfate's primary purpose is to treat and accelerate healing of duodenal and gastric ulcers through local cytoprotective action at the ulcer site, forming a protective barrier against acid, pepsin, and bile salts. 1
Mechanism of Action
Sucralfate works through local rather than systemic action after oral administration, as it is only minimally absorbed from the gastrointestinal tract. 1 The drug achieves its therapeutic effect through several complementary mechanisms:
- Forms an ulcer-adherent complex with proteinaceous exudate at the ulcer site, creating a physical barrier that protects against further damage from acid, pepsin, and bile salts 1, 2
- Binds and inactivates pepsin in gastric juice (inhibiting pepsin activity by 32% at therapeutic doses) and adsorbs bile salts 1, 3
- Stimulates mucosal defense mechanisms including prostaglandin release, bicarbonate secretion, mucus production, and epithelial cell renewal 4, 2
- Increases local fibroblast growth factors which promote mucosal healing 4
The drug has minimal acid-neutralizing capacity (14-16 mEq per 1g dose), confirming its action is primarily protective rather than antacid. 1
Primary Clinical Indications
Peptic Ulcer Disease (First-Line Historical Use)
- Duodenal and gastric ulcer healing: Sucralfate 1g four times daily is effective for healing ulcers over 4-8 weeks, with efficacy comparable to H2-receptor antagonists like cimetidine 3, 5
- Current positioning: Proton pump inhibitors (PPIs) are now recommended as first-line agents, with sucralfate serving as a second-line alternative when PPIs or H2-blockers cannot be used 6, 7
Radiation Proctitis (Specialized Indication)
- Sucralfate enemas are specifically recommended for managing chronic radiation-induced proctitis with rectal bleeding 8
- The enemas control bleeding by stimulating epithelial healing and forming a protective barrier over damaged rectal mucosa 6, 9
- This represents one of only four treatments with randomized trial evidence for radiation-induced bleeding 8
Stress Ulcer Prophylaxis (Second-Line Role)
- PPIs and H2-receptor antagonists are first-line agents for stress ulcer prophylaxis in critically ill patients 6, 9
- Sucralfate is recommended as a second-line option, particularly in patients at high risk for ventilator-associated pneumonia, as it may carry lower pneumonia risk compared to acid-suppressive therapies 6, 9
- However, sucralfate was associated with higher rates of clinically significant GI bleeding compared to ranitidine in one large trial 9
Important Clinical Caveats
What Sucralfate Does NOT Do Effectively
- Not effective for NSAID-related gastric ulcers - PPIs are preferred 7
- Oral sucralfate is NOT recommended to prevent radiation-induced diarrhea during pelvic radiotherapy, as it does not prevent acute diarrhea and may cause more GI side effects including rectal bleeding 8
- Not effective for radiation-induced oral mucositis prevention or treatment 6
Administration Considerations
- Must be given at least 2 hours apart from PPIs or H2-blockers to avoid interaction, as these acid-suppressive drugs can interfere with sucralfate's mechanism 9, 7
- For H. pylori-associated ulcers, eradication therapy must be used in addition to sucralfate 7
Safety Profile
Sucralfate is exceptionally well-tolerated with minimal systemic absorption. 1, 3 The most common side effect is constipation, occurring in only 2% of patients. 3 This excellent safety profile makes it particularly valuable during pregnancy for acid-related diseases. 4